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Acidity and Undissociated Acid

A weak acid has a pKa of 3.654. If the solution pH is 3.741, what percentage of the acid is undissociated?

A weak acid has a pKa of 5.857. Calculate the pH of a solution in which the ratio of the concentrations of acid anion to undissociated anion ([A-]/[HA]) equals 7.555.

Solution Preview

Ka = [H][A]/[HA] for a monoprotic acid

pka =-logKa = -log[H][A]/[HA] = pH - log[A]/[HA]

log[A]/[HA]=pH-pka

[A] =x amount of acid dissociated

[HA] = U-x U is original amount of the acid before dissociation occurs

U-x is also the ...

Solution Summary

This solution is provided in approximately 275 words. It calculates step-by-step the amount of acid dissociated and undissociated, and calculates pH.

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